If the customer requests the data be deleted, the encryption keys are erased, leaving the data unreadable in the cloud.
"The file server is a gateway to the cloud," said Andres Rodriguez, CEO of Nasuni. "We're caching to the cloud. You can have 1TB of data in an appliance managing a much bigger amount of data in the cloud."
Nasuni customers can also choose a policy that allows them to retrieve deleted encryption keys, so that if they're mistakenly deleted, they're not permanently removed.
Like the latter vendors, Cirtas sold appliances for data centers that accelerated data transfers to cloud storage providers. The company had only come out of quiet mode last September and had raised $32.5 million in venture funding.
Cirtas is not the first heavily-financed storage service provider to hit difficult times. A decade ago, StorageNetworks Inc., which offered online primary storage, got more than $200 million from Dell, Compaq Computer and others in venture funding and another $243 million from an initial public offering. Three years later, it closed.
Officials at Iron Mountain, Amazon S3, and AT&T could not immediately be reached for comment.
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